Watch: The story behind the Imperial State Crown

The body of Queen Elizabeth II has been lying-in-state at Westminster Hall since Thursday, ahead of the Queen’s funeral today. The Queen’s coffin has been draped with the Royal Standard, a white floral wreath with flowers from both Balmoral and Windsor Castle, and the Imperial State Crown atop a purple velvet cushion since her body arrived in London from Balmoral since last week.

The current Imperial State Crown was originally created for the coronation of the Queen’s father, King George VI, in 1937 but the crown has existed in various forms since the 15th century.

About 10 versions of the crown have existed since the restoration of the monarchy in 1660, with the latest version based on the one made for Queen Victoria in 1838.

Queen Elizabeth II then wore the Imperial State Crown at her own coronation at Westminster Abbey on 2 June, 1953.

After the official coronation ceremony, the Queen entered St Edward's chapel at Westminster Abbey to swap the St. Edward’s crown (the heaviest of Her Majesty’s three coronation crowns at 2.23kg) for the Imperial State Crown, and change into the robe of purple velvet for the final procession.

What are the jewels in the Queen’s crown?

The crown is made of pure gold and set with 2,868 diamonds, 269 pearls, 17 sapphires, 11 emeralds, and four rubies, but it also contains some of the most famous individual jewels in the Crown Jewels collection.

The Stuart Sapphire, a 104-carat stone set at the back of the crown, is thought to have belonged to King Charles II and may have originated from Asia.

The Imperial State Crown also includes the Cullinan II diamond, a 317.4-carat diamond from the original Cullinan diamond, the largest gem-quality rough diamond ever found, which was originally discovered in Cullinan, South Africa, in 1905.

Meanwhile, the St Edward’s Sapphire, an octagonal rose-cut sapphire that sits in the centre of the cross at the top of the crown, is older than any other gemstone in the royal collection and is thought to have belonged to Edward the Confessor, one of the last Anglo-Saxon English kings.

Lastly, the Black Prince's Ruby, a 170-carat cabochon spinel, takes pride of place on the Imperial State Crown. It has been in the possession of England’s rulers since 1367, when it was given to Edward of Woodstock – who was known as the 'Black Prince', most likely because of his distinctive black armour and/or jousting shield.

How much is the Queen’s crown worth?

The Imperial State Crown doesn’t have an exact value attached to it. Along with other Crown Jewels the Imperial Orb and Imperial Sceptre, it has never been appraised.

Although the Imperial State Crown doesn’t have a precise value, due to its extensive list of priceless gems, jewellery experts estimate the crown to be worth an eye-watering £3 billion to £5 billion.

The Imperial State Crown also features a purple velvet cap with an ermine border and is lined with white silk and was present at every State Opening of Parliament, worn by the Queen each year.

Even on occasions when Her Majesty could not wear it, or on the one occasion that her son, the now-King Charles III, attended in her place, it was still present at the State Opening.

The original crown, created for King George VI was slightly taller than the one that the Queen wore during her 70-year reign.

The crown was adjusted for Her Majesty's coronation in 1953. The head size was reduced and the arches were lowered by 25 mm (one inch) to give it a more feminine appearance, according to Anna Keay, author of The Crown Jewels.

“You see, it’s much smaller isn’t it?” the Queen told the BBC in 2018 on a look back at her coronation.

“It would have been up to about there when my father wore it,” she continued, pointing to the top of the diamond-encrusted orb on top.

The Queen also called the crown “very unwieldy” due to its weight, adding that she couldn’t put her head down to read a speech, but had to bring the speech to her eye line.

“Fortunately, my father and I had the same sort of shaped head, but once you put it on it stays,” she added. “It just reigns itself.”

Will King Charles III wear the Queen’s crown?

It remains to be seen whether King Charles III will use the Imperial State Crown for his own coronation and reign, but given its rich history with his mother, and grandfather before him it would be the appropriate choice.

Also, given the weight of some of the other, sold-gold crowns, the Imperial State Crown is also the most practical.

The coronation of King Charles III will not be for a few months, and until the official ceremony, he will not be able to wear any of the crowns in the Crown Jewels.

As the crown was adjusted for the Queen from its original form, it looks like it would also be able to be adjusted for the King in the time leading up to his coronation, once the date is confirmed.

Her Majesty is to lie in wait in Westminster Hall for four days, until her funeral on Monday.

For the procession, the late Majesty’s coffin was borne on a Gun Carriage of The King’s Troop Royal Horse Artillery – poignantly used for the coffins of the late Queen’s mother and father.

The coffin was draped with the Royal Standard, a flag representing the four kingdoms of the UK which is also used at royal residences when the sovereign is home.

Also on the coffin was a white floral wreath which featured white roses, white dahlias and foliage, including pine from the gardens at Balmoral and pittosporum, lavender and rosemary from the gardens at Windsor.